Ammunition



Patented Mar. 7, 1933 UNITED STATES PATENT orrlcr.

JAMES E. BURNS, OF BBIDGEPOBT, CONNECTICUT, ASSIGNOR TO REMINGTON ARMS COMPANY, INC., A CORPORATION OF DELAWARE AMMUNITION No Drawing.

The present invention relates to priming mixtures for ammunition. Morespecifically, the invention pertains to priming mixtures of the non-corrosive type which are characterized by the absence of ingredients which would leave residues of a hygroscopic na-- ture in the gun bore, which residues would attract moisture and promote a ravaging corrosion on the steel of the bore. Such noncorrosive mixtures are to be distinguished from corrosive priming mixtures which have contained such an ingredient as potassium chlorate. long known to be in a large measure responsible for the corrosion which sometimes occurs in gun barrels subsequent to firing.

Effortsto combat the evil of corrosion in gun bores have led to the substitution, for the corrosive potassium clilorate,'of one or more non-corrosive oxidizers, such :for example as barium-nitrate and/or lead nitrate. By the use of non-corrosive oxidizing ingredients,

' however, it hasbecome-necessary to change other ingredients of the priming mixture because of certain characteristics of these noncorrosive oxidizing ingredients. In the corrosive type primers it has been customary to use potassium chlorate as theoxidizing ingredient for the reason, among others, of its exceptional ability to yield a large amount of oxygen at comparatively low temperatures. Fulminate of mercury has been long used with potassium chlorate as'the flame initiating ingredient therefor. When a noncorrosive oxidizing ingredient, such as barium nitrate, is used, it is sometimes desirable to select other flame initiating ingredients. Fulminate of mercury is essentially a detonating substance, and, when used in amounts large enough to develop sufficient heat for liberating the oxygen from the barium nitrate, has been found to develop forces of detonation in a degree such as to be undesirable for ammunition primers.

Successful non-corrosive priming mixtures have been produced in the past by the substitution, for a part of the fulminate of mercury, of the ingredient lead styphnate, known also as lead trinitroresorcinate Application filed March 24, 1980. Serial No.,438,628.

when used with a non-corrosive oxidizing ingredlent, such as barium nitrate. Successful non-corrosive priming mixtures have been obtained also by eliminating mercury fulmi-- nateentirely, and utilizing instead, as an auxiliary flame initiating ingredient and sensitizing agent for the lead trinitroresorcinate, one of the substances known as tetracenes, such as guanylnitrosaminoguanyltetracene (C H ON This substance is especially desirable for use in priming mixtures because it is non-mercuric, and because tutes a highly eflicient substitute for leadtrinitroresorcinate in priming mixtures, particularly non-corrosive mixtures. In addition to the fact that basic lead picrate is easier and safer to manufacture, it possesses the further advantage over lead trinitroresorcinate of being less sensitive to friction while possessing aboutthe -same sensitiveness to shock. I

Basic lead picrate of the formula (3 H N0 OPbH,

may be produced for example, by a process such as is described in the patent/to F riedrich, No. 1,478,429, December 25, 1923; and this material may be used for the purposes of the present invention. It is preferred, however, to use di-basic lead picrate of the formula:

either as an alternative for or in admixture with basic lead picrate of the formulae given above. Dibasic lead picrate of the last mentioned formula may be prepared, for example, as follows:

Picric acid in the amount of about 4.6

grams is dissolved in about 60 c. c. of a 4% A solution of sodium hydroxide, and this sop crate generally, including the lution is added, as by dripping, to a solution of about 10.75 grams of lead nitrate in about 300 c. c. of water. The first solution is permitted to remain at room temperature,

1 while the lead nitrate solution is maintained at a temperature preferably between and 60 C. and is stirred during the addition of the first solution. About .9 gram of dexdroxide also appear to be present. Whether 1 this product is a compound ofv definite composition or is a mixture of compounds has not been ascertained with certainty. it has been definitely demonstrated, in connection with the discoveries of thepresent invention, that when this product is used in priming mixtures as described herein, new I and improved results are obtamed'as 118115111 set forth. It is to be understood that the term basic lead picrate as used in this specbasic lead dibasic lead picrate as well as the monobasic salt. It will be further understood that the terms basic lead picrate and dibasic lead picrate as herein used refer. to substances composed chiefly of these monobasic and dibasic lead salts of pic'ric acid, whether or not small amounts of other materials are to be found in these substances.

According to the present invention, it has been discovered that improved priming mixtures are tobe obtained by the use of basic ification and claims refers to lead picrate admixed with an additional flame initiating or sensitizing ingredient such as guanylnitrosaminoguanyltetracene and /or mercury fulminate, and used with a non-corrosive oxidizing ingredient such, for example, as barium nitrate and/or lead nitrate. Lead peroxide may also be used successfully in some mixtures containing basic lead picrate. In some mixtures it may be found desirable to add one or more fuel ingredients such, for-example, as lead sulphocyanate and/or antimony sulphide and/or calcium silicide, although with many mixtures this is not essential. Basic lead picrate, besides serving in the capacity of a flame initiating ingredient, is found also to serve excellently in the capacity of a fuel, and it has been found that successful mixtures may be ob- 'ent-s, such as abrasives and binders,

However, I

use of, basic lead picrate in priming mixtures with or without the use of additional fuel ingredients. The usual auxiliary ingredicourse be used where found to be desirable.

A mixture which has given good results in non-corrosive center-fire ammunition 18 as follows:

v 7 Per cent Mercury fulminate, approximately... 20 Basic lead picrate, approximately ..v 20 Barium nitrate, approximately 36.5 Lead peroxide, approximately--. Antimony sulphide, approximately 9 Calcium silicide, approximately 7.5

A mixture utilizing basic lead picrate in admixture with guanylnitrosaminoguanyltetracene which has given good results in noncorrosive rim-fire ammunition is as follows:

Another successful rim-fire mixture is as follows:

Per cent Guanylnitrosaminoguanyltetracene, ap-

proximately 3 Basic lead picrate, approximately 45 Barium nitrate, approximately 26 Lead sulphocyanate. approximately 8 Abrasive, approximately 18 A mixture which has given good results in may of Successful non corrosive priming mixtures utilizing basic leadpicratein admixture with mercury fulminate may be prepared as follows: I

7 Per cent Mercury fulminate 15-40 Basic lead picrate"... 5-20 Barium nitrate 25- 40 Abrasive 15-35 Binder v .5-- 2 A typical mixture which has given good re- 1 sults in non corrosive rim-fire ammunition is as follows:

Y Per cent Mercury fulminate, approximately 25 Basic lead picrate, approximately 15 Barium nitrate, approximately 34 I Abrasive, approximately 25 Binder, approximately 1 non-corrosive:center-fire ammunition is as follows:

. Per cent Guanylnitrosaminoguanyltetracene approximately 2 Basic lead picrate, approximately 25 Lead nitrate, approximately 55 Calcium silicide, approximately 8 Lead sulphocyanate, approximately 10 The terms sensitizing ingredient and flame initiating ingredient as used in this specification and appended claims are to be understood in the sense in which they are ordinarily used by ammunition chemists; that is, as defining compounds which in and of themselves and apart from other materials are susceptible to explosive combustion and decomposition into simpler compounds or elements under the stimulus of heat and/or friction, and as excluding substances which for their decomposition or reaction under such stimulus require the presence of a second and difierent material.

11. A priming mixture for ammunition having substantially the following composition:

Per cent Mercury fulminate, approximately 25 Basic lead picrate, approximately 15 Barium nitrate, approximately 34 Abrasive, approximately 25 Binder, approximately ,1

12. A priming mixture for ammunition having substantially the following compositionf Per cent Guanylnitrosaminoguanyltetracene, ap-

proximately 2 Basic lead picrate, approximately 2.--- 25 Lead nitrate, approximately 55 Calcium silicide, approximately 8 Lead sulphocyanate, approximately 1O JAMES E. BURNS.

It will be understood that many variations Y may be made without departing from the scope of the invention as defined in the following claims.

.What is claimed is 1. A priming mixture for ammunition containing basic lead picrate in admixture with V guanylnitrosaminoguanyltetracene.

2. A priming mixture for ammunition containing dibasic lead picrate admixed with guanylnitrosaminoguanyltetracene.

3. A riming mixture for ammunition containing asic lead picrate, guanylnitrosaminov guanyltetracene, and barium nitrate.

4. A priming mixture for ammunition containingbasic lead picrate, guanylnitrosaminoguanyltetracene, barium nitrate, and a fuel.

, 5. A priming mixture for ammunition containing basic lead picrate, guanylnitrosaminoguanyltetracene, and lead nitrate.

6. A priming mixture for anmiunition containing basic lead picrate, guanyln-itrosaminoguanyltetracene, lead nitrate, and a fuel.

7. A priming mixture for ammunition containing basic lead picrate, guanylnitrosaminoguanyltetracene, lead nitrate, lead sulphocyanate, andcalcium silicide.

8. A priming mixture for ammunition containing basic lead picrate admixed with mercury fulminate.

9. A priming mixture for ammunition containing dibasic lead picrate, mercury ful minate, and an oxidizer.

'10. A priming mixture for ammunition 7 comprising: r

' g Per cent Mercury fulminate 15-40 Basic lead picrate 5-20 Barium nitrate 25-40 Abrasive 15-35 Binder .5- 2 

